Dynamic display alignment with left and right image overlay

Abstract

Improved techniques include providing a coupling element on a nose bridge that can overlay left and right images output from respective outcouplers and send the overlay image to a sensor. Based on at least a portion of the overlay image, the sensor may cause the left, right, or both field of views to move until the left and right images are aligned.

What is claimed is: 
     
         1 . A head-mounted wearable device, including:
 a frame worn by a user, including:
 a projection system configured to emit internally generated radiation to a left waveguide and a right waveguide; 
 the left waveguide, including:
 a left incoupler configured to couple the internally generated radiation and externally generated radiation into the left waveguide to produce left radiation in the left waveguide; 
 a left outcoupler configured to couple the left radiation in the left waveguide out of the left waveguide to produce left outcoupled radiation, the left outcoupled radiation representing a current left image; 
 
 the right waveguide, including:
 a right incoupler configured to couple the internally generated radiation and externally generated radiation into the right waveguide to produce right radiation in the right waveguide; 
 a right outcoupler configured to couple the right radiation in the right waveguide out of the right waveguide to produce right outcoupled radiation, the right outcoupled radiation representing a current right image; 
 
 a coupling element coupled to the left outcoupler and the right outcoupler, the coupling element configured to combine the left outcoupled radiation and the right outcoupled radiation to produce a current overlay image; 
 a sensor element coupled to the coupling element, the sensor element configured to determine a degree of misalignment of the current left image and the current right image based on a difference between the current overlay image and an initial overlay image, the initial overlay image being a combination of an initial left image and an initial right image at an initial calibration. 
   
     
     
         2 . The head-mounted wearable device as in  claim 1 , wherein the frame further includes a nose bridge, and the sensor element is located in an interior of the nose bridge. 
     
     
         3 . The head-mounted wearable device as in  claim 1 , wherein the current left image is a left point spread function resulting from a left pointwise impulse and the current right image is a right point spread function resulting from a right pointwise impulse; and
 wherein the degree of misalignment of the current left image and the current right image is based on a difference between the left point spread function and the right point spread function.   
     
     
         4 . The head-mounted wearable device as in  claim 1 , wherein the projection system is further configured to perform an offset of a field of view of the current left image and/or the current right image to produce an aligned image. 
     
     
         5 . The head-mounted wearable device as in  claim 4 , wherein the offset of the field of view is performed by a proportional-integral-derivative (PID) loop of the sensor element. 
     
     
         6 . The head-mounted wearable device as in  claim 1 , further comprising an angled coupler coupled to the left outcoupler, the angled coupler being configured to couple the left outcoupled radiation into the coupling element from the left waveguide at a range of angles. 
     
     
         7 . The head-mounted wearable device as in  claim 1 , wherein the head-mounted wearable device is configured to power off in response to the degree of misalignment being greater than a threshold. 
     
     
         8 . A method, comprising:
 receiving an initial overlay image, the initial overlay image being a combination of an initial left image and an initial right image at an initial calibration;   causing internally generated radiation to be emitted by a projection system into a left waveguide and a right waveguide within a frame of a head-mounted wearable device, the left waveguide including a left outcoupler configured to couple left radiation in the left waveguide out of the left waveguide to produce left outcoupled radiation, the left outcoupled radiation representing a current left image, the right waveguide including a right outcoupler configured to couple right radiation in the right waveguide out of the right waveguide to produce right outcoupled radiation, the right outcoupled radiation representing a current right image; and   determining, via a sensor element, a degree of misalignment of the current left image and the current right image based on a difference between a current overlay image formed by a coupling element and the initial overlay image, the coupling element coupled to the left outcoupler and the right outcoupler, the coupling element configured to combine the current left image and the current right image to produce the current overlay image.   
     
     
         9 . The method as in  claim 8 , wherein the frame further includes a nose bridge, and the sensor element is located in an interior of the nose bridge. 
     
     
         10 . The method as in  claim 8 , wherein the current left image is a left point spread function resulting from a left pointwise impulse and the current right image is a right point spread function resulting from a right pointwise impulse; and
 wherein the degree of vertical misalignment of the current left image and the current right image is based on a difference between the left point spread function and the right point spread function.   
     
     
         11 . The method as in  claim 8 , further comprising performing an offset of a field of view of the current left image and/or the current right image to produce an aligned image. 
     
     
         12 . The method as in  claim 11 , wherein the offset of the field of view is performed by a proportional-integral-derivative (PID) loop. 
     
     
         13 . The method as in  claim 8 , further comprising coupling the left outcoupled radiation into the coupling element from the left waveguide at a range of angles. 
     
     
         14 . The method as in  claim 8 , further comprising:
 performing a power off operation in response to the degree of misalignment being greater than a threshold.   
     
     
         15 . A computer program product comprising a nontransitory storage medium, the computer program product including code that, when executed by processing circuitry, causes the processing circuitry to perform a method, the method comprising:
 receiving an initial overlay image, the initial overlay image being a combination of an initial left image and an initial right image at an initial calibration;   causing internally generated radiation to be emitted by a projection system into a left waveguide and a right waveguide within a frame of a head-mounted wearable device, the left waveguide including a left outcoupler configured to couple left radiation in the left waveguide out of the left waveguide to produce left outcoupled radiation, the left outcoupled radiation representing a current left image, the right waveguide including a right outcoupler configured to couple right radiation in the right waveguide out of the right waveguide to produce right outcoupled radiation, the right outcoupled radiation representing a current right image; and   determining, via a sensor element, a degree of misalignment of the current left image and the current right image based on a difference between a current overlay image formed by a coupling element and the initial overlay image, the coupling element coupled to the left outcoupler and the right outcoupler, the coupling element configured to combine the current left image and the current right image to produce the current overlay image.   
     
     
         16 . The computer program product as in  claim 15 , wherein the frame further includes a nose bridge, and the sensor element is located in an interior of the nose bridge. 
     
     
         17 . The computer program product as in  claim 15 , wherein the current left image is a left point spread function resulting from a left pointwise impulse and the current right image is a right point spread function resulting from a right pointwise impulse; and
 wherein the degree of vertical misalignment of the current left image and the current right image is based on a difference between the left point spread function and the right point spread function.   
     
     
         18 . The computer program product as in  claim 15 , wherein the method further comprises performing an offset of a field of view of the current left image and/or the current right image to produce an aligned image. 
     
     
         19 . The computer program product as in  claim 18 , wherein the offset of the field of view is performed by a proportional-integral-derivative (PID) loop. 
     
     
         20 . The computer program product as in  claim 15 , wherein the method further comprises coupling the left outcoupled radiation into the coupling element from the left waveguide at a range of angles. 
     
     
         21 . The computer program product as in  claim 15 , wherein the method further comprises:
 performing a power off operation in response to the degree of misalignment being greater than a threshold.